New Study Sheds Light on Understanding “Calcium Taste”

Having too much of a good thing can quickly turn bad.

Love tomatoes or carrots? Well, if you consume way too many, you just might give yourself a nice orange glow. Drinking water is essential to life. But if you’re an overachiever and drink an extreme amount in a short time, it can cause the level of salt, or sodium, in your blood to drop too low, causing hyponatremia—which can ultimately be fatal.

Moderating the “good” things in life seems to pertain to everything, even calcium.

In a new study published in the journal Neuron, biologists were able to enhance the scientific understanding of why and how animals and humans have a “calcium taste”.

The study states, “calcium is something of a double-edged sword. Too much of the essential element is as dangerous as too little, either case adversely affects health in animals from human to mice to fruit flies.” So, having a biological alarm system to say when calcium is low or high is crucial. However, it doesn’t fit into the already five established tastes that the tongue’s receptors can identify—sweet, sour, salty, bitter, and savory.

The new research conducted by researchers at the University of California, Santa Barbara (UCSB) and colleagues in Korea found that calcium taste also exists in fruit flies. They also discovered a unique class of gustatory receptor neurons (GRNs), which is necessary for calcium taste in organisms. However, the flies were indifferent to low calcium and averse to high levels. This was surprising, considering that some calcium is necessary to sustain life.

“We wanted to understand the underlying mechanisms used to respond to the presence of calcium in food,” said senior Craig Montell, UCSB’s Duggan Professor of Molecular, Cellular, and Development Biology and Neuroscience. “We not only identified the taste neurons but also found three receptor proteins that are important in sending calcium. In fact, eliminating any one of them allowed us to do an interesting survival experiment.”

Using petri dishes with one side containing solely fructose and the other a mix of sugar and high level of calcium, researchers found that normal flies who rejected the high-calcium side and ate only pure fructose survived. They then took mutant flies, which have had any one of the three newly found GRNs removed, and observed that they were unable to distinguish the two halves of the petri dish. This showed that they had consumed enough of the calcium to cause viability problems, which resulted in an early death.

“It turns out that fruit flies don’t have a mechanism for sensing low calcium even though it’s good for them, but they are trying to guard against consuming too much calcium,” Montell said. “Surprisingly, we found that calcium avoidance occurred through two mechanisms: activation of a unique class of GRNs, distinct from those that sense bitter compound and which cause a stop-feeding signal when activated. In addition, calcium inhibits sugar-activated GRNs,” he added.

“In humans, high calcium is associated with many diseases and can even be life threatening. Our results suggest that calcium taste might function primarily as a deterrent in a wide range of animals, including humans.”

To say the least, living life with moderation is always a good rule to live by.

Calcium is used for more than just sustaining life. Drugs are often chemically made into their salt forms to enhance how the drug dissolves and to boost its absorption into your bloodstream. This includes the use of calcium as the salt accompanying the active pharmaceutical ingredient (API). API is the part of any drug that produces the its intended effects.

Phenomenex set out to optimize the U.S. Pharmacopeial Convention (USP) method for analyzing Atorvastatin Calcium—supplements used to help lower “bad” cholesterol and fats and raise “good” cholesterol in the blood. It belongs to a group of drugs known as “statins.” It works by reducing the amount of cholesterol made by the liver.

According to the original USP monograph for atorvastatin calcium, the method has a run time of 115 minutes. Phenomenex scientists set out to minimize that runtime without sacrificing resolution.